Intermittent cooling system



c. G. MUNTERS 2,023,088

INTERMITTENT COOLING SYSTEM Filed Feb. 9, 1955 INVEN TOR.

Ca/I/C Sim y 9724mm ATTORNEY.

Patented Dec. 3, 1935 UNITED. STATES PATENT OFFICE signor, by mesne assi gnments, to Serve], Inc.,

Dover, Del., a corporation of Delaware Application February 9, 1933, Serial No. 655,881

6 Claims.

This invention relates generally to refrigeration, more particularly to intermittent refrigeration systems and still more particularly to the intermittent cooling of objects or apparatus required to be alternately heated and cooled.

An object of my invention is to provide a cooling system automatically operable to intermittently cool a heat rejecting body. Another object of my invention is to provide for alternate heating and cooling of a generator-absorber of an intermittent refrigeration system without use of valves. A further object is to hold up or elevate liquid for obtaining control or regulation of a refrigeration system without mechanical parts.

For an understanding of this invention, reference may be had to the following description taken in connection with the accompanying drawing in which,

The figure shows schematically a circulating liquid cooling system applied to the generatorabsorber of an intermittent absorption refrigerating apparatus in a manner taught by this invention.

Referring to the drawing, a generator-absorber I is of any construction suitable for use in an intermittent absorption refrigerating apparatus, the other parts of which are not shown since such systems are well known in the art and do not enter into the present invention. The generatorabsorber, as illustrated schematically, comprises a fluid tight casing I I enclosing a horizontally elongated chamber [2 in which is contained a suitable absorbent as, for instance, calcium chloride into which a suitable refrigerant as, for instance, ammonia, is absorbed during the r'efrigerating period of the apparatus and expelled therefrom during the heating or generating period. The generator-absorber is heated by a burner 53 arranged so that the burner flame projects into a flue M which extends through chamber l2 and is provided on the opposite end from the burner with an upwardly extending extension l5 through which the products of combustion are discharged after further utilization of the heat thereof as hereinafter described.

Connection for the generator-absorber to the 'condenser and evaporator of the refrigerating system (not shown) is provided by conduit "5. Around the generator-absorber easing II is pro-. vided a jacket I! which is connected into the ,cooling liquid circuit as hereinafter described.

Preferably the whole generator-absorber including the cooling jacket i1 is surrounded with a covering of heat insulating material l8.

Above the generator-absorber I0 is located a cooling element H! which may be provided with a cooling coil or jacket as well known in the art or, as illustrated, provided with a good heat radiating surface consisting of fins 20 for cooling by heat transfer to the air. The upper part of the generator-absorber cooling jacket I! is connected through conduit 2| to one end of the cooling element l9 and the other end of the latter is connected through a coil 22 around the fiue extension l5 and a U-tube liquid trap conduit 23 to the lower part of jacket H. The jacket l1, cooling element I9, and coil 20 connections form a closed cooling system which is filled with a suitable heat conducting liquid as for instance ethylene glycol or paraflin oil.

with the inter- The coil 22 is arranged in good heat exchange relation with the flue extension l5 for the purpose hereinafter set forth.

In operation, the generator-absorber is first heated to expel refrigerant vapor from the absorber, the vapor passing through conduit Hi to a condenser where it is liquefied and conducted to an evaporator. After substantially all of the refrigerant has been expelled from the absorbent, 25

heating is discontinued and the absorbent cooled, thereby decreasing the pressure in the system so that the liquid refrigerant evaporates in the evaporator and is again absorbed in the generator-absorber. known in the art, may be provided for the heating element to change from the generating to the refrigerating periods and reverse. The refrigerating appa atus and its control, however, are not part of this invention except for the cooling of the generator-absorber.

Suitable control means, well Cooling liquid in jacket I'I around the generator-absorber casing H is heated by the transfer of heat of absorption from the absorbent in chamber l2 during the refrigerating period. The cooling liquid becomes lighter due to this increase of temperature in jackets I! and rises through conduit 2| to the cooling element l9 and is replaced by cool liquid from conduit 23.

' In the cooling element l9 heat is dissipated from the cooling liquid to the air or other cooling medium through the heat radiating fins 20. The cool liquid, being heavier than the warm liquid in jacket I! and conduit 2|, descends through coil 22 and conduit 23 back to the jacket l1. Thus there is a continuous circulation of cooling liquid through jacket I1 during the refrigerating period.

When the' burner I3 is lighted at the beginning of the generating period, the cooling liquid in jacket I! continues to receive heat and tends to rise in conduit 2|. However, due to the heat exchange relation between coil 22 and the flue extension IS, the cooling liquid in this portion of the circuit is also heated and tends to rise. Coil 22 is designed such that the tendency of liquid to flow upwardly in conduit 2| is balanced by the tendency of liquid to flow upwardly in coil 22, in other words, such that the liquid columns on both sides of the U-bend 23 are of the same weight. As a result, no liquid circulation takes place in the cooling circuit during the heating or generating period. The cooling jacket l'l around the generator-absorber is preferably constructed very narrow so that a minimum amount of cooling liquid is in heat exchange relation with the generator-absorber during the heating period. Such reduction in the heat capacity of the liquid in the cooling jacket naturally gives higher efliciency of operation.

It will be obvious to those skilled in the art that various other changes may be made in the construction and arrangement without departng from the spirit of the invention and therefore the invention is not limited to what is shown in the drawing and described in the specification but only as indicated in the following claims.

I claim:

1. In refrigeration apparatus of the intermittent absorption type including a generator-absorber, a jacket around said generator-absorber, a heat dissipating element at a level above said generator-absorber, a rising conduit from the upper part of said jacket to said element, and a continuously descending return conduit from said element'connected to the lower part of said jacket'forming a closed circuit containing a nonvolatile heat conducting liquid, and means for heating said return conduit during the generating period.

2. In refrigeration apparatus of the intermittent absorption type including a generator-ab sorber, means forming a closed liquid circuit containing a nonvolatile liquid and having a heat dissipating portion at a level above said generator-absorber and forming a liquid column on each side of said heat dissipating portion, one of said columns extending in heat transfer relation with said generator-absorber, and. means 5 for heating the other of said columns during the generating period.

3. Refrigeration apparatus of the intermittent absorption type including a generator-absorber,

a heating flue for the latter, means to heat in said flue, and means forming a closed liquid circuit having aheat dissipating portion at a level above said generator-absorber and forming a liquid column on each side of said portion, one of said columns extending in heat transfer relation with said generator-absorber, and said flue extending in heat transfer relation with the other 01' said columns.

4. An intermittent cooling system comprising means forming a closed liquid circuit having an upper heat dissipating portion between two upright portions and containing a nonvolatile liquid, one of said upright portions being adapted for heat transfer from an object to be cooled, and means for intermittently heating the other of said upright portions.

5. A method of intermittent cooling which comprises circulating liquid in a closed circuit having a heat dissipating portion, causing said circulation by heat tra'nsferfrom an object to be cooled to the liquid in a rising portion of the circuit; and intermittently interrupting said circulation by exerting a force tending to cause circulation in the opposite direction.

6. A method of intermittent cooling which comprises circulating liquid in a closed circuit having a heat dissipating portion, causing said circulation by heat transfer from an object to be cooled to the liquid in a rising portion of the circuit, and intermittently interrupting said circulation by heating liquid in such other portion of said circuit that circulation tends to be reversed. 

